Apparatus for the catalytic conversion of hydrocarbons



June 13, 1950 E. w. SHAND 2,511,652

APPARATUS FOR THE CATALYTIC CONVERSION OF HYDROCARBONS Filed June 3,1947 HYDROGARBON OUTLET VALVE FLUE GAS REGENERATING SECTIONREGENERATION/ 5 SECTION AIR 8 l6 7 9 2 CATALYST RETURN l0 13 I2 l 4CATALYST FEED u HYDROGARBON INLET INVENTOR.

EDWIN W. SHAND MAW Patented June 13, 1950 APPARATUS FOR THE CATALYTICCONVER- SIGN OF HYDROCARBON S Edwin W. Shand, Homewood, Ill., assignorto Sinclair Refining Company, New York, N.'Y., a

corporation of Maine Application June 3, 1947, Serial No. 752,239

2 Claims.

This invention relates to the pyrolytic conversion of hydrocarbons andmore particularly apparatus adapted to carry on pyrolytic conversionprocesses involving the use of catalysts.

In the conversion of hydrocarbon base stocks to produce products havingdesired properties, such as high octane number for use in gasoline, thestock is subjected to one of several processes, such as cracking,hydrogenation, dehydrogenation, etc., in the presence of the catalystadsorbed on a carrier.

After such catalysts have been in use for a period of time, they must beregenerated by removing the carbon which becomes deposited on thecatalyst in use. This is generally accomplished by burning the carbondeposit from the catalyst which results in the liberation of heat.

An object of the present invention is the provision of means forcarrying out conversion processes in which the heat of the spentcatalyst and the heat liberated in the regeneration of the catalyst ismore effectively employed to maintain the desired temperature in thereactor or converter in which the conversion operation is performed. Theinvention contemplates the delivery of charge oil and fresh orregenerated catalyst to the bottom of a reactor or converter, thecontinuous feed of fresh or regenerated catalyst to the bottom of thechamber thereby forcing the catalyst in the chamber upwardly and meansfor delivering the catalyst from the top of the chamber, at which timeit is ready for regeneration, in such manner that the heat thencontained in the catalyst and the heat created in the regeneration ofthe catalyst can be employed for heating the chamber. The treated stockpasses through the catalyst bed to an outlet at the top whence it isconveyed to condensers, stabilizers, separators or fractionators orother apparatus.

The catalyst, moving upwardly in the chamber, overflows into an annularspace surrounding the reactor. In the upper part of this annular chamberthe catalyst freshly discharged from the reactor, being hot, helps tomaintain the desired heat conditions in the reactor. The catalyst movesdownwardly in the annular space by gravity. The lower portion of theannular space, which is separated from the upper portion by suitablevalve mechanism, forms the regenerating chamber and means are providedfor delivering air thereto and removing flue gases therefrom. Theregeneration of the catalyst supplies heat which also serves to maintainthe required temperature in the reactor. From the regenerator thecatalyst may be returned by suitable means, such as a screw conveyor tothe bottom of the reactor.

In the accompanying drawing I have illustrated one form of apparatussuitable for use in practicing the invention.

In the drawing the figure is a vertical section illustrating, more orless diagrammatically, the practice of the invention.

Referring to the drawing, I provide an inner chamber I shown as circularbut which may be of any suitable shape which is adapted to contain thecatalyst substantially filling the entire chamber. The bottom of thechamber is preferably tapered or funnel shaped as indicated at 2. Asecond chamber 3 surrounds the chamber I, the second chamber beingdivided into an upper portion 4 and a lower portion 5 by a partition 6.Suitable valve means 1 may control communication between the chambers 4and 5.

The lower chamber 5 which is the catalyst regenerating chamber, isprovided with a sloping bottom 8 and an outlet pipe 9 is connected tothe lowest point of the bottom 8. This pipe communicates with a conveyorconsisting of a cylindrical casing l0 and a shaft carrying a screw I I,the shaft and the screw of the conveyor being rotated by any suitablemeans. For purposes of illustration, I have indicated a pulley I2 on theshaft which may receive a belt from any suitable source of power. Theoutlet end of the conveyor communicates with a pipe I3 extending intothe funnel-shaped bottom of the chamber I.

An inlet pipe I4 for the stock to be treated communicates with thebottom of the pipe I3 and an outlet pipe I5 for the treated stockcommunicates with the top of the chamber. The catalyst regeneratingchamber is provided with an inlet pipe I6 for air and an outlet pipe I!for flue gases.

In practicing the process the chamber I is filled with fresh catalystand brought to the temperature necessary for the particular conversionprocess to be performed. Suflicient additional catalyst is fed to theconveyor [0 and thence to the bottom of the chamber I to cause thecatalyst in the top of the chamber I to overflow into the annular space4. Periodically, the catalyst contained in the space 4 is delivered tothe regenerating chamber 5 by opening the valves I. Air is thendelivered to the regenerating chamber through pipe I6 and flue gasesdischarged therefrom through pipe I1. The stock to be treated isdelivered to the reactor through pipe I4. It passes up through the bedof catalyst wherein the desired conversion operation is performed and,

is discharged through outlet pipe l5. From pipe IS the treated stock isdelivered to fractionators, separators or other apparatus depending uponthe particular conversion process being performed.

While the process is in operation catalyst may be continuously fed tothe bottom of the chamber I and it continuously overflows from the topof the chamber intothe annular. space 4. The rate of feed may beregulated, according to the particular catalyst being used, so that thetime of travel through the chamber I is the time that such catalyst isnormally used'priorto regeneration. The catalyst material overflowinginto chamber 4 is thus in condition for regeneration at the time that itis automatically fed from the reactor. With the continuous feed ofcatalyst from chamber 4 to the regenerating chamber 5, the valves 1 aremaintained in open position. Admixture of flue gases with thehydrocarbon vapors in the upper part of the reactor may be prevented byproper balancing of pres,- sures. A pressure of from 5 to 25 lbs. persq. inch may be maintained the top of the reactor andvalves I kept openwithout admixture ;of. the flue gases and the stock, by maintainingsubstantially the same pressure, or a slightly lower pressure invchamber 5.

Valves 1 may be normally closed and periodi cally, w hen a quantity, ofcatalysthas accumulated in the chamber 4,-,theva,l ves 1, opened todeliver catalyst to-the regenerating chamber 5. Passage of flue gasesintothe chamber 4. and

thence to the regenerator may be. prevented by using .double valves, orby discontinuing, deliveryof air. hroughpipe |6,-whi1e:valves, I areopen.

,Air, at the necessary temperatures for regeneration of the catalyst, isdeliveredto the regenerating, chamber through pipe .7 l6. The 7 carbonis thus burned ofiof the catalystand a, portion of the heat createdpasses through the wallof :the reactor chamber to heat the catalyst bedin, the chamber. From the chamber 5;the.cataof; the ,regenerator, moves.the:,;catalyst.. bed. .up-

wardly and causes. the .catalyst'at the top to. over,- flow intothechamber 4.

, The inventionmay-be employed in any of the conversion processesusingsanyof the known catalyst .inwhichthe catalyst is in granular .orpelletform ornin whichatheicatalyst isiinuthe form of a .metal ormetaloxide coating on grant ber, a mechanical conveyor connected at itsoutlet end with the lower end of the inner chamber and'adaptedforcefully to feed catalyst thereto, a conduit leading from a lower zoneof the outer chamber to the-inlet end of the conveyor, an inlet forpassingthe hydrocarbon charge oil into the lowerend'of the innerchamber, an outlet for withdrawing products of the conversion from theupper end of the outer chamber, and conduit means for passing air intoand for Withdrawing flue gas from the outer chamber.

2. Apparatus foifluse in the conversion of hydrocarbonsin thecprcsenceof a catalyst and for regenerating the catalyst comprising a verticallyelongated conversion chamber adapted to'be filled with a granularcatalyst, an outer chamber surrounding the first said-chamber anddivided into an: upper and lower. zone, the inner chamber opening atits. upper end into the upper zone of the outervchamber, a passagewayconnecting the upper zone with the .lower zone-of'the outer chamber,valve means so constructed'and arrangedas to regulate the size of andto-cl0se the passageway a mechanical conveyor con nected'at its outletend with the-lower end'of the inner chamber and adapted forcefully tofeed catalyst thereto, a conduit leading from the lower zone of theouter chamber-to the-inlet end of the conveyor, aninletforpassinghydrocarbon charge oil to the lower end of the inner cham ber, anoutlet for withdrawing products of the conversion from the upper-end ofthe outer chamber,- an inlet'for regenerating gas'at the lower end andan outlet for flue-gas at the upper end of the lower zone ofthe outerchamber. 4

-EDWIN'W. SHAND.

EEFEBJENCESNCITEDI I I The following references'are 'of 'record in thefile ofthispatent: 7

UNITED STATES PATENTS Number Name Y Date 2,337,684 Scheineman Dec. '28,1943 2,378,342 Voorhees et a1. June 12, 1945-

1. APPARATUS FOR USE IN THE CONVERSION OF HYDROCARBONS IN THE PRESENCEOF A CATALYST AND FOR REGENERATING THE CATALYST COMPRISING A VERTICALLYELONGATED CONVERSION CHAMBER ADAPTED TO BE FILLED WITH A GRANULARCATALYST, AN OUTER CHAMBER SURROUNDING THE FIRST SAID CHAMBER, THE INNERCHAMBER OPENING AT ITS UPPER END INTO THE OUTER CHAMBER, A MECHANICALCONVEYOR CONNECTED AT ITS OUTLET END WITH THE LOWER END OF THE INNERCHAMBER AND ADAPTED FORCEFULLY TO FEED CATALYST THERETO,